This invention relates in general to a support platform for a computer keyboard or the like and, more particularly, to a tilt control or pitch control mechanism for a keyboard support platform. The tilt control mechanism of the present invention permits the selective adjustment of the pitch or tilt of the support platform to allow the user to set the work angle of the keyboard.
The keyboard support platform construction is of the type generally shown in McConnell, U.S. Pat. No. 5,037,054 and U.S. Pat. No. 5,145,136, or Smeenge et al., U.S. Pat. No. 4,616,798. The aforesaid McConnell and Smeenge patents are incorporated herein by reference. Typically, a keyboard support platform is attached by parallel and/or non-parallel pivotal linkage arms to a slidable plate. The slidable plate, in turn, is mounted in a slide on the underside of a desk or other work surface. The slide permits the keyboard support platform and linkage to move between a storage position or retracted position to an extended or use position. The conventional pivotal linkage arms further permit the keyboard support platform to be adjusted to a useful operational work height.
The conventional keyboard support platform assemblies, however, are limited in the degree of keyboard tilt. That is, known keyboard platform assemblies limit the operational work angle of the keyboard and, therefore, do not ergonomically comply with the requirements of all users. Because conventional keyboard support platform assemblies are so limited, keyboard users have suffered from various debilitating medical conditions. As an example, it has been shown that without the proper work angle setting of the keyboard, users who perform considerable data entry on the keyboard have suffered from Carpal Tunnel Syndrome which is a medical disorder of the hand that creates numbness and pain in the fingers. Consequently, there is a need for an improved keyboard support platform assembly which provides not only adjustable work height of the keyboard but also improved adjustment of the tilt or work angle of the keyboard to prevent such debilitating medical conditions.
The present invention recognizes and provides a solution to the aforementioned problems associated with the known keyboard support platform assemblies. Accordingly, it is an object of the present invention to provide an improved adjustable support mechanism for a keyboard support platform. It is a further object to provide an adjustable tilt control mechanism which permits the user to set the pitch or angle of the keyboard support platform.
Briefly, in summary, the present invention comprises a tilt control mechanism for a keyboard support platform. The keyboard support platform is of the type that includes a linkage for connecting the platform to a work surface. The linkage further includes linkage arms which pivotally connect the keyboard support platform to the work surface. The tilt control mechanism comprises a keyboard support platform bracket having a tilt pivot axis connection to the linkage arms, and a tilt adjustment actuator arm pivotally attached at a fulcrum point at one end to the pivot axis connection. Connected between the actuator arm and support platform is a pawl and ratchet. The pawl and ratchet connection define distinct length actuator arm connections between the fulcrum point and the support platform to thereby control the tilt or pitch of the platform.
The full range of objects, aspects and advantages of the invention are only appreciated by a full reading of this specification and a full understanding of the invention. Therefore, to complete this specification, a detailed description of the invention and the preferred embodiment follows, after a brief description of the drawing.